CMAQ tracer namelist for CO2

Hi everyone, I am trying to use tracer namelist to add CO2 and CH4 in CMAQ runs. But I can’t understand the official tutorial, the tutorial made me very confused…
Would anyone provide me with a tracer namelist for CO2 or CH4.
I would really appreciate it.

Thank you in advance,

Example tracer namelist files are provided with the code according to this link.

The tracer namelist is generally interchangable between mechanisms. It can be employed for transport and deposition studies. Example tracer namelists are under $CMAQ_MODEL/CCTM/src/MECHS/trac0 (the version most often used) and $CMAQ_MODEL/CCTM/src/MECHS/trac1.

Thank you very for your reply!
I have read many examples for tracer namelist, but confused me very much!
I really need a exact namelist just for CO2 simulation.
Would you please provide it for me?

Some additional information from @mathur.rohit

For CO2, I would turn on all transport operators - advection, hdiff, vdiff, and cloud transport. Of course CO2 will be emitted but our emissions do not have CO2. I am not sure we model CO2 dry dep, so that is something the user will need to think about as well as any dissolution to cloud water (Henry law constant; likely small). Similarly, CO2 uptake by the biosphere (photosynthesis) will need to be represented and thus far we have not made those process enhancements.

In short, if the user has CO2 emissions the tracer nml can certainly be modified for initial transport tests (essential first step) but more needs to be done for other processes.